On the mechanics of stress-induced phase transformation in zirconia

Some consequences of a simple theoretical model for the stress-induced, isothermal phase transformation of an isolated tetragonal zirconia crystal are studied. The transformation to a monoclinic state is viewed as mechanical buckling from one homogeneous geometrical configuration to another. The model is used to predict the manner in which an applied shear stress should interact with hydrostatic stress in causing the transformation, and also the reverse monoclinic-to-tetragonal phase change. An isolated tetragonal inclusion in an elastic matrix is also considered, and its response to a far-field combination of shear and hydrostatic stress is analysed.